Runner attachment for bicycle-frames.



No; 737,372. PATENTED AUG. 25,1903.

RDUPRAS.

RUNNER ATTACHMENT FOR BICYCLE FRAMES.

' APPLICATION FILED APR. 11, 1903.

N0 MODEL.

WITNESSES: /NVENTOR A TTOHNE VS UNITED STATES Patented August 25, 1903PATENT OFFICE.

RUNNER ATTACHMENT FOR BICYCLE-FRAMES.

SPECIFICATION formingpart of Letters Patent No. 737,3'72, dated August25, 1903.

Application filed April 11, 1903- .To all whom, it may concern.-

Be it known that I, FREDERICK DUPRAS, a citizen of the United States,and a resident of Marquette, in the county of Marquette and State ofMichigan, have made certain new and useful Improvements in RunnerAttachments for Bicycle-Frames, of which the following is aspecification.

It is the object of my invention to provide an improved runnerattachment for the ordinary bicycle-frame, the attachment including adriving mechanism which is operated by the ordinary chain-and sprocketgear employed on bicycles.

The details of construction, arrangement, and combination of parts areas hereinafter described, reference being had to accompanying drawings,in which Figure 1 isa side view of a bicycle-frame provided with myimproved attachment. Fig. 2 is an enlarged transverse vertical sectionon the line 2 2 of Fig. 1. Fig. 3 is a detail view illustrating the lockof the propelling-wheel. Fig. 4 is an enlarged cross-section of the rearrunner and attachments.

In the drawings, A indicates the front runner, and B the rear runner, ofmy improved attachment, the same being each formed of a steel bar, whichis bent slightly upward at the front end and preferably groovedlongitudinally. The front runner A has two inclined legs or posts a,which are provided at their upper ends with a hub a, through whichpasses an axle c, whereby the runner is duly connected with the frontfork c of the bicycleframe 0. In practice the ends of the fork 0' willfit in socket-pieces and the cylindrical portions of the axle passthrough both parts, the portion passing through the hub a being square.The runner A is thus adapted to oscillate in a vertical plane and turnlaterally with the front fork in the same manner as the wheel usuallyemployed in its place.

The rear runner B is similar to the front one in so far as relates tothe inclined legs or posts 6. It has in addition a central vertical postor leg I), whose upper end b (see Fig. 2) is enlarged and bored to adaptit to receive and support the rotatable hub of the rear axle d. Thelatter is suitably held in the rear fork c of the frame C in such man-Upon said axle is ner that it cannot rotate.

Serial No. 152,176- (No model.)

mounted a loose or rotatable sleeve or hub 6, having twosprocket-wheelsfand f secured on its respective ends. Between therunnerhub and sprook etsff antifriction-balls are provided and alsobetween the rotatable hub or sleeve 6' and the axle d, as shown in Fig.4. The friction due to oscillation of the rear runner-B on the loose hube and of the latter on the fixed axle d is thus reduced to a minimum. Asshown in Fig. 1, a chain 71. runs from the left-hand sprocketf to alarger one i, which is keyed on the driving-axle j, to which cranksbearing pedals are applied in the usual Way. Ball-bearings are providedfor the driving-axle in the frame-hanger in the usual way.

The means for propelling the bicycle with the runner above described areas follows: A

toothed or spur wheel D is arranged in a vertical slot in the rearrunner B and the central post b, the toothed portion of said Wheelprojecting below the runner proper, so as to take into the ice or snowsurface on which the attachment is used. This propellingwheel ispreferably triangular in shape, as shown. The axle of said spur-wheel Dis journaled in the central post 1) near the runner B. A chain is runfrom sprocket-wheel f of the rotating hub e to a smaller wheel Z, keyedupon the axle of spur-wheel D, and it is hence apparent that the latteris driven from the crank-shaftj on the end of the axle of wheel D.Opposite the sprocket-wheel Z is keyed a notched wheel m, with which aslidable pawl n is adapted to engage for the purpose of locking thespur-Wheel D, as hereinafter described. The said pawl n slides inkeepers 0, projecting from the side of the vertical post 12, and aspiral spring p is arranged between said keepers, as shown in Fig. 2.The pawl 'n is also provided with across-pin r for limiting thedownwardmovement of the spring. The pawl is square in cross-section, so that itcannot rotate in the keepers. A cord or strap 8 is attached to the upperend of the pawl and extends through suitable guides 25 to a lever it,which is pivoted on the top bar of the bicycle-frame C. When the leverto is thrown down and secured by suitable fastening 'v, as shown in Fig.1, the pawl n is raised out of engagement with the toothed wheel m, andthe spur-wheel D is thus left free to rotate for driving thesled. Uponreleasing the leveru the expansion of the spring p throws the pawl downinto engagement with the toothedwheel m, whereby the spurgearD islocked, so that it cannot rotate. The arrangement of the notches inwheel m with relation to the three sides of the spurwheel D is such thatwhenever the pawl is engaged with the wheel m one of the sides of thespur-wheel D is flush with the end surface ofthe runner B. In thisposition the attachmentis properly adjusted for coasting. It will beunderstood that in order to again propel the sled the lever u must bethrown down and secured, as in Fig. 1, for the purpose of releasing thelock of the spur-wheel D and leaving the latter free to rotate.

A strap 5 (see Fig. 1) connects the front end of the rear runner B withthe bicycleframe, and thus serves as a guard, limiting the oscillationof the runner within the limits of safety.

Having thus described my invention, what I claim as new, and desire tosecure by Letters Patent, is-

1. The combination with a bicycle-frame having front and rear axles anda driving crank-shaft, of front and rear runners journaled and adaptedto oscillate in the front and rear forks, the rear runner having avertical slot, a spur driving-wheel journaled in the slot and having asprocket-wheel keyed on its axle, a hub journaled on the rear axle, andhaving two sprocket wheels, a third sprocket-wheel keyed on thecrank-shaft of the frame, and chains connecting the several sprockets,substantially as shown and described.

2. The combination with the bicycle-frame and the usual drivingmechanism comprising the crankshaft, sprocket-wheel and chain, of therear-runner attachment hereinbefore described comprising an axle fixedin the rear fork, a hub journaled on said axle and provided withsprocket-wheels, the runnerpost having an enlarged cylindrical head, andantifriction-balls between the same and the aforesaid hub and in thespacev between the latter and the axle, a toothed drivingwheel journaledon the runner proper, a sprocket-wheel which is fast with saiddriving-wheel, and a chain extending therefrom to one of the sprocketsof the said hub, substantially as shown and described.

3. The combination with the rear runner of the spur-wheel journaledthereon in a Vertical plane and means for rotating the same, the saidspur-wheel having three plane sides, a toothed wheel keyed upon theaxleof said spur-wheel, a locking device adapted to en- .gage saidtoothed wheel and means for releasing the lock.

4. The combination, with a suitable frame, and a rear runner adapted tooscillate'in said frame, of a triangular propelling-Wheel which isjournaled in connection with said runner, a toothed wheel which is fastwith said propelling-wheel, a slidable pawl adapted to engage thetoothed wheel, a spring applied to the said pawl, and means under thecontrol of the operator for raising the pawl out of engagement with thetoothed wheel, substantially as shown and described.

5. The combination. with a suitable frame and a runner connectedtherewith, of a polygonal propelling-wheel journaled on said runner,means for rotating said propellingwheel, and means for looking it withone of the sides parallel with the under surface of the runner,substantially as shown and described.

FREDERICK DUPRAS.

